JP2017223210A - Two-piece housing connecting rod l-shaped yoke opposing piston type stroke capacity continuous variable device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To resolve a problem requiring a balancer reducing high vibration due to the fact that a crank rotation angle at a piston descending side becomes wider than that of piston ascending side to cause crank balance to be disturbed and the high vibration to be generated in the prior art in which oscillating axis center positions of arms for restricting motions at the crank sides of the two-piece housing oscillatable connecting rods are changed to enable their strokes to be changed continuously.SOLUTION: This invention relates to an opposed piston engine having two crank shafts oppositely rotated under the same number of revolutions in which crank sides of the two-piece housing oscillatable connecting rods are applied as L-shaped yokes that variable control arm connecting axis centers are arranged at couple apexes where diagonals become substantially right angle in respect to a side connecting the crank pin axis centers, the arm connecting shafts are stroked by the variable control arms in an arc-shaped manner and the oscillating axis center positions of the variable control arms are variably controlled in a two-dimensional manner in such a way that their trajectories are changed in their positions and angles in a radial manner within a range of Λ-shape that approaches to a top dead center side and widens to both sides at a bottom dead center in respect to a line substantially in parallel with the cylinder center axis passing through the crank journal axis center.SELECTED DRAWING: Figure 1-1

Description

In the present invention, the stroke volume and compression ratio are continuously and continuously variable at any time in an engine such as an automobile, and the stroke rotation angle on the piston descending side (intake and expansion strokes) is wider than that on the ascending side (compression and exhaust strokes). The present invention relates to compactness, low center of gravity, and vibration reduction in a continuously variable device.

The stroke volume and compression ratio of the internal combustion engine with respect to the output are the main factors that determine the thermal efficiency and pumping loss.If the stroke volume and compression ratio can be selected continuously according to the load, the rotational speed, etc. Increases thermal efficiency and reduces pumping loss.
Patent document US Pat. No. 4,433,596 which converts piston reciprocating motion into crankshaft rotational motion with a swash plate (slanted shaft), changes the tilt angle and crankshaft direction position of the swash plate (slanted shaft), and varies the stroke volume and compression ratio. No. 2004-245092, etc., but it has a large mechanical loss at the part that converts the piston reciprocating force into the rotational force of the output shaft, and it is difficult to achieve high rotation. The mechanism that changes the angle of inclination) is also inadequate in terms of accuracy and safety. A single swash plate, with multiple cylinders arranged around the crankshaft in parallel with the crankshaft, The moment of inertia tends to be unbalanced, and it is very difficult to balance with a single-shaft crank. In addition, cylinders, cylinder heads, etc. are arranged in order in the crankshaft direction, and the axial engine length becomes longer. Therefore, it is difficult to arrange the crankshaft and transmission in the left-right direction of the vehicle body. However, the actual situation is that it has not been put into practical use because there are many disadvantages that obstruct the driver's and passenger's seats due to the overhang of the transmission portion into the cab.

If a single crank mechanism is applied, conventional processing equipment can be used, and the engine layout is similar, so that it can be easily mounted on a conventional vehicle body and the barrier to practical use is reduced.
Dividing the connecting rod into two parts, mainly restricting the movement on the crank side with the arm, and changing the position of the swing axis of the arm, or making the swing axis move circularly with 1/2 rotation of the crank, variable compression ratio Many proposals have been made to realize a so-called Atkinson cycle in which the stroke is variable for each rotation of the crank.
Among them, in the second quadrant inside the perpendicular to the core shaft passing through the cylinder core shaft and the crank journal shaft, a swing shaft core of an arm for restricting the movement of the crank side connecting rod is provided. No. 2003-129817 and JP-A-2003-201875, the piston stroke can be continuously changed by changing the pivot axis position one-dimensionally or two-dimensionally, and the compression ratio is also matched to the stroke volume. There has been proposed one that can be set or arbitrarily continuously variable at any time.

In Japanese Patent Application Laid-Open Nos. 2003-129817 and 2003-201875, a swing tip shaft is provided together with a swing shaft core of an arm in the second quadrant, and the locus of the tip shaft determines the piston stroke. The two-way connecting rod connecting shaft runout in the direction perpendicular to the cylinder is similar to the crankpin rotation diameter. However, the crankpin rotation diameter can be made somewhat smaller than the piston stroke, but the piston side pressure can be reduced compared to the conventional single crank mechanism, but greatly. The crank-side connecting rod is elongated in the direction perpendicular to the cylinder, causing an increase in the weight of the reciprocating motion, resulting in an increase in vibration and a decrease in strength, and a change in the top dead center phase of the piston stroke. Accordingly, VVT for adjusting the valve timing is indispensable, and if the valve timing is also variable, a VVT having a larger phase variable width is required. Further, the crank rotation angle on the piston lowering side (intake and expansion strokes) is wider than that on the ascending side (compression and exhaust strokes), which is advantageous in terms of combustion efficiency. The crank arrangement of this type had a drawback that the crank balance was not achieved and the vibration was large.

The present invention has been made in view of the above-described problems. The crank side of a connecting rod that is divided into two and is connected so as to be swingable in a direction perpendicular to the crankshaft is connected to the side connecting the connecting shaft and the crankpin axis. Cylinder core shaft with L-shaped yoke with variable control arm connection shaft core at the opposite vertex where the diagonal is approximately right angle, stroke the arm connection shaft in an arc shape with the variable control arm, and the path passes through the crank journal shaft core The position of the swing axis of the variable control arm is adjusted so that the position and angle change in a radial manner within a square shape that approaches the top dead center side and spreads on both sides on the bottom dead center side. By dimensionally variable control, the stroke volume is continuously variable continuously, and the compression ratio is set according to the stroke volume, or can be arbitrarily continuously variable at any time to improve thermal efficiency and reduce pumping loss in a wide operating range. Along with being able to figure out Side stroke can be greatly reduced with low mechanical loss, top dead center phase change when stroke is variable, VVT is not required for phase alignment, and the stroke volume continuously variable device can suppress the increase in reciprocating motion part weight. Two cranks that are reverse to each other in number are arranged in parallel, the pistons connected to each crank are opposed to each other on a concentric shaft, and the position of the swing axis of the variable control arm is opposed to the two cranks. By variably controlling on the opposite side of the cylinder to a line symmetrical position with respect to the intermediate line perpendicular to the line connecting the two crank journal axes, vibration in the direction perpendicular to the cylinder axis remains slightly, but the cylinder axis direction Stroke volume series suitable for automotive engines that can achieve a balance, greatly reduce vibration, eliminate the need for a balancer device, and achieve compactness in the crankshaft direction and low center of gravity. There is provided a variable device.

In order to solve the above-mentioned problem, the invention of claim 1 is such that the crank side of the connecting rod, which is divided into two parts and is swingably connected in the direction perpendicular to the crankshaft, is diagonal with respect to the side connecting the connecting shaft and the crankpin axis. An L-shaped yoke is provided with a variable control arm connection axis at the opposite vertex that is substantially perpendicular, and the arm connection axis is stroked in an arc shape by the variable control arm, and the locus is substantially parallel to the cylinder axis passing through the crank journal axis. The position of the swing axis of the variable control arm is two-dimensionally adjusted so that the position and angle are changed radially within a square-shaped range that approaches the top dead center side and spreads on both sides on the bottom dead center side. In the variable control, two cranks that are reverse to each other at the same rotational speed are arranged in parallel, the pistons connected to the cranks are opposed to each other on the concentric shaft, and the swing axis position of the variable control arm is Paired against two cranks In the opposite side of the piston cylinder, characterized in that the stroke volume continuously variable device for variably controlling arranged in line symmetry with respect to perpendicular median line to the line connecting the two crank journal axis.
Conventional two-division connecting rod stroke volume variable mechanisms such as Japanese Patent Application Laid-Open Nos. 2003-129817 and 2003-201875 are located on the piston side of the connecting rod connecting shaft, so that the cylinder skirt portion can be It is necessary to prevent contact, and there is a disadvantage that the connecting rod on the piston side becomes long, and the connecting rod on the crank side is also extended in the direction perpendicular to the cylinder core axis, which causes an increase in vibration and strength due to an increase in weight and an increase in engine block. It was.
Although the crankpin rotation diameter can be made somewhat smaller than the piston stroke, the deflection width in the direction perpendicular to the cylinder core axis of the connecting rod connecting shaft is equal to the crankpin rotation diameter. Although the side pressure due to piston slap can be reduced, it cannot be significantly reduced, and the top dead center phase of the piston stroke changes greatly as the stroke changes. Therefore, VVT is essential to match the valve timing, and the valve timing is also reduced. If variable, VVT having a larger phase variable width is required.
In addition, since the crank rotation angle on the piston lowering side (intake and expansion strokes) is wider than that on the ascending side (compression and exhaust strokes), it is advantageous in terms of combustion efficiency, but it is frequently used in engines such as automobiles. The crank arrangement of 6 etc. has a disadvantage that the crank balance is not balanced and the vibration becomes large.
As in the present invention, the connecting rod is divided into two and connected so as to be swingable in the direction perpendicular to the crankshaft, the movement on the crank side is restricted by a variable control arm, and the position of the swing axis of the arm is variable two-dimensionally. With the piston stroke continuously variable, arm connecting shafts are provided at the opposite vertices whose diagonal is substantially perpendicular to the side connecting the connecting rod connecting shaft and the crankpin shaft core (the crank pin shaft and the arm connecting shaft core). Connecting rod connecting shaft cores are provided at positions extending substantially perpendicularly from the arm connecting shaft core to the line connecting them, and three shaft cores are arranged in an L shape), and the arm connecting shaft is stroked in an arc shape by the arm. The position and angle change in a radial manner within a square-shaped range that approaches the top dead center side and spreads on both sides on the bottom dead center side with respect to a line that is substantially parallel to the cylinder core axis passing through the crank journal axis. By doing Since the connecting rod connecting shaft draws a stroke on the arc connecting locus of the arm connecting shaft in such a way that the connecting rod connecting shaft swings with respect to the arm connecting shaft, the vibration in the direction perpendicular to the cylinder core shaft is minimized, and the piston slap The side pressure due to can be greatly reduced, resulting in low mechanical loss. In this example diagram, priority is given to forming the cylinder mating surface only with the upper crankcase and facilitating surface machining, so the connecting rod connecting shaft stroke trajectory in the minimum and maximum stroke is the maximum in the direction perpendicular to the cylinder shaft. The cylinder core shaft is disposed at a position slightly deviated from the approximate center of the swing width, and the deflection of the connecting rod connecting shaft in the direction perpendicular to the cylinder core shaft is slightly increased. As the processing man-hours increase, it becomes easier to create a step on the mating surface during assembly, and it is necessary to take care of the liquid seal. However, if the cylinder mating surface machining is performed simultaneously with the middle case, the cylinder core axis is perpendicular to the cylinder core axis. It is easily possible to make it the approximate center of the maximum swing width.
Also, in order to set the compression ratio according to the stroke amount, the position perpendicular to the cylinder core shaft at the top dead center of the arm connecting shaft will be slightly shifted, but the displacement is small, so at the top dead center due to the stroke amount. The change in the crank phase is small and is within a few degrees, and VVT for timing adjustment is not necessary.
In addition, since the arm connecting shaft is sandwiched between the crankpin shaft and the cylinder skirt in the vicinity of the top dead center, the height of the cylinder head mating surface with respect to the crank journal shaft is higher than that of the single crank mechanism, The crank pin rotation radius of the single crank mechanism is 1/2 of the stroke, but it can be reduced to about 1/3 to 1/4 of the maximum stroke, so it is not so high, and the connecting rod connecting shaft position relative to the arm connecting shaft is a cylinder. Since the connecting rod connecting shaft position does not decrease to the crank pin rotation radius even at the bottom dead center side, the connecting rod length can be made shorter than that of the single crank mechanism, which is more advantageous than the patent literature example in terms of strength and weight. Can be.
In addition, by making the variable control arm's pivot axis position variable in a planar shape (two-dimensional), the compression ratio can be varied continuously and steplessly at any time over the entire stroke range. High compression ratio in the low load and low rotation region on the stroke volume) side to improve combustion efficiency, and low compression ratio to prevent knocking in the high load and low rotation region on the maximum stroke (maximum stroke volume) side In addition to being able to change the compression ratio in a stepless manner, the variable range of the compression ratio can be set to a large value, so it is not necessary to continuously and continuously adjust the compression ratio of a supercharged gasoline engine to the compression ratio of a diesel engine or HCCI engine with a single engine. The stage can be changed.
In the stroke volume variable mechanism having the above-described features, two cranks that are reverse to each other at the same rotational speed are arranged in parallel, and the pistons connected to the cranks are opposed to each other on the concentric shafts to swing the variable control arm. An opposed piston type in which the dynamic axis position is arranged on the opposite side of the opposed piston cylinder with respect to the two cranks, and is variably controlled to a line symmetric position with respect to an intermediate line perpendicular to the line connecting the two crank journal axes. By using a continuously variable stroke volume device, the crank rotation angle on the piston lowering side (intake and expansion strokes) is wider than that on the ascending side (compression and exhaust strokes), which is advantageous in terms of combustion efficiency. The straight 4 and straight 6 crank arrangements have the disadvantage that the crank balance is not balanced and the vibration becomes large. With Linda core axial direction balanced significantly reducing vibration and can be made balancer required, the cylinder axis direction is becomes long can be made compact crankshaft direction than the series engine of the same number of cylinders.
In addition, by reversely rotating the crank with two cranks, it is possible to cancel the gyro effect of the engine part and make the engine suitable for the crankshaft arrangement in the longitudinal direction of the vehicle body, and the position of the swing axis of the variable control arm relative to the two cranks The piston on the piston lowering side (intake and expansion stroke) is arranged on the opposite side of the opposed piston cylinder and is variably controlled in a line-symmetrical position with respect to the intermediate line perpendicular to the line connecting the two crank journal axes. The stroke characteristics in which the rotation angle is wider than the ascending side (compression, exhaust stroke) can be set to the same for both cylinders, and the dimensions perpendicular to the cylinder core axis can be made compact and the center of gravity can be lowered.
The crank rotation angle between the top dead center and the bottom dead center when the crank pin rotates on the cylinder side with respect to the crank journal shaft becomes wider, and the bottom dead center from the top dead center when the crank pin rotates on the opposite side of the cylinder Because of the characteristic that the crank rotation angle is narrow, the piston core shaft that is opposed by a single crank is shifted in the direction of the crankshaft on the same line as viewed from the crankshaft direction as in the case of the conventional opposed piston. In the layout in which the swing axis position of the arm is arranged on the opposite side of the opposed piston cylinder with respect to the crank, and is variably controlled to a line symmetrical position with respect to a line passing through the crank journal axis and perpendicular to the cylinder axis, Since the connected crank pins rotate in the same direction, if the crank rotation angle between the top dead center and the bottom dead center of one piston is wide, the top of the piston on the opposite side With narrower becomes the combustion characteristics crank angle between the bottom dead center vary considerably from point, is not balanced inertial force can also difference reciprocator. By using two cranks and rotating in reverse at the same rotation speed, the stroke characteristics of both cylinders can be made the same, and the combustion characteristics and crank balance can be combined.

According to a second aspect of the present invention, in the first aspect of the present invention, the swing shaft of the variable control arm is pivotally supported by a link in a V shape when viewed from the crankshaft direction, and can be positioned and fixed by three-point support. The tip of the link close to the crankshaft core with respect to the pivot axis position of the variable control arm is meshed with a male feed screw shaft that is arranged parallel to the line connecting the two crank journal shaft cores and perpendicular to each crank journal shaft. The female feed screw is pivotally supported by the matching female feed screw, and the female feed screw is slid on the male feed screw shaft by the rotation of the male feed screw shaft by restricting the rotation of the female feed screw by the link. The stroke volume is mainly changed by changing the axial center position mainly in the cylinder axis parallel direction.
As a method for pivotally supporting the swing shaft of the variable control arm by changing the position, the swing shaft is pivotally supported at the end of the feed screw shaft as in Japanese Patent Application Laid-Open Nos. 2003-129817 and 2003-201875. There are methods to change the position one-dimensionally with a feed screw, or to make the phase of the feed screw shaft variable and make it variable two-dimensionally, but it is necessary to provide a feed screw and gears for each cylinder, cost, alignment This is disadvantageous in terms of accuracy, and the feed screw shaft itself moves, resulting in a large inertia when the stroke volume is variable. When the phase is variable, inertia including a case for holding the mechanism is added, resulting in a problem of a decrease in response speed.
As in the present invention, by pivotally supporting the swing axis of the variable control arm with a V-shaped link, it can be pivotally supported by three-point support with the end shafts of both links, in terms of cost and alignment accuracy. The movable part inertia of the variable mechanism is small, the response speed can be increased, and the mechanism can be stored in the crankcase, so that liquid sealing is easy.
In order to hold the rocking shaft stably and reliably, the triangle formed by the rocking shaft and the tip shafts of both links maintains the triangle in the entire variable stroke (stroke volume) range and the rocking shaft core. The interior angle of the point must be 0 ° and away from 180 °.
In addition, when changing the swing axis position two-dimensionally, the stroke volume (piston stroke) is mainly variable by moving the tip of the link side that displaces the swing axis of the variable control arm mainly in the cylinder axis direction. However, the compression ratio also changes due to the cylinder core axis perpendicular displacement, and the compression ratio is mainly changed by moving the tip of the link side that is displaced in the cylinder core axis perpendicular direction. Since the stroke volume also changes, when the stroke volume is accurately varied at a determined compression ratio, it is necessary to coordinate both link tip end movements.
The piston stroke mainly varies depending on the position of the variable control arm swing axis in the cylinder core direction. The larger the displacement of the cylinder core axis position, the greater the stroke can be varied. The distal end of the link to be displaced is connected to a female feed screw that meshes with a male feed screw shaft that is parallel to the line connecting the two crank journal shaft cores, that is, parallel to the cylinder core shaft and perpendicular to each crank journal shaft. By pivotally supporting the shaft and restricting the rotation of the female feed screw with the link, the female feed screw slides on the male feed screw by the rotation of the male feed screw, thereby changing the position of the pivot axis. Thus, the moving amount can be increased and the stroke volume variable amount can be increased. Further, since the feed screw portion is irreversible transmission, the stroke volume can be kept constant without power, and the power consumption can be suppressed and the fuel consumption can be reduced.

According to a third aspect of the present invention, in the invention of the second aspect, the opposed piston mechanisms are arranged side by side in the crankshaft direction, and the male feed screw near the intermediate line perpendicular to the line connecting the two crank journal shaft cores. A gear is provided on the shaft, the feed screws on both sides of the gear are reverse screws, and an idle gear is arranged in the middle of the male feed screw shaft for each cylinder row to form a gear train. A driven gear is provided at the end of the shaft that extends in parallel with the male feed screw shaft from the gear end, and the drive volume of the variable stroke volume control motor is engaged to interlock the stroke volume variable mechanism for each opposed piston cylinder row. The variable control of all the cylinder rows can be performed with one motor.
By arranging the gear train near the center of the two crank journal shafts, it can be arranged without interfering with the sliding of the female feed screw, and it is arranged avoiding the swing axis movement and swing range of the variable control arm The shaft formed integrally with the idle gear that transmits the power from the variable stroke volume control motor is arranged by effectively utilizing the space between the male feed screw shafts arranged for each cylinder row, thereby widening the cylinder row interval. Without the female feed screw that slides on the male feed screw shaft, it can be arranged.

According to a fourth aspect of the present invention, in the first aspect of the present invention, the swing shaft of the variable control arm is pivotally supported by a link in a V-shape when viewed from the crankshaft direction and can be positioned and fixed by three-point support. The tip of the link far from the crankshaft center of the swing axis of the variable control arm is pivotally supported by the tip of the arm fixed in each cylinder row to the shaft arranged in parallel for each of the two crankshafts. In addition, the compression ratio can be changed mainly by changing the position of the swing axis of the variable control arm mainly in the direction perpendicular to the cylinder axis by swinging the tip of the control lever fixed to the shaft. And
Although the compression ratio mainly varies depending on the cylinder axis perpendicular position of the variable control arm swing shaft, the displacement amount can be smaller than the variable piston stroke, so a feed screw mechanism is provided for each cylinder employed for variable stroke volume. The shaft is arranged parallel to each crankshaft, and the eccentric shaft or separate arm formed integrally with the shaft for each cylinder is fastened to the shaft, and the shaft phase is varied. Changing the position perpendicular to the cylinder axis by changing the position of the link axis perpendicular to the cylinder axis by changing the position of the cylinder axis perpendicular to the cylinder axis is superior in terms of cost, weight, and assembly. Can be made compact. However, if the shaft cannot be placed on the crankcase mating surface, the shaft should be slid in the axial direction and inserted into the shaft hole of the crankcase. It is necessary to limit the amount of directional displacement or to thicken the shaft to a shaft diameter that can secure the amount of eccentricity. The cylinder axis perpendicular displacement of the oscillating shaft for varying the compression ratio is almost proportional to the piston stroke variable, that is, the cylinder axis parallel displacement, so if the piston stroke variable is large as in this proposal, the eccentric shaft Then it becomes difficult to cope.
By adopting a system in which a separate arm is fastened to the shaft when the shaft is inserted into the crankcase, the arm length can be changed regardless of the shaft shaft diameter, and the displacement in the direction perpendicular to the cylinder axis can be increased, resulting in a large variable piston stroke. Can handle variable compression ratio.

According to a fifth aspect of the present invention, in the fourth aspect of the invention, the feed screw for converting the rotation of the compression ratio control motor into a linear motion and swinging the compression ratio variable control lever is provided with two crank journal shaft cores. Near the middle line perpendicular to the connecting line, it is arranged at a substantially right angle to the shaft axis and the line connecting the shaft axes on both sides to which the control lever is fixed, and at least one of the joints connecting the leading end of the feed screw and both control levers. It is characterized in that the length can be adjusted and the double cylinder compression ratio can be synchronized.
By arranging the feed screw near the middle of the two cranks, the compression ratio control mechanism including the feed screw can be placed in the space between the journal shafts of both cranks, the crankcase can be made compact, and the joint length of one side By changing the phase, the phase of the compression ratio control lever can be adjusted, and the compression ratio of both cylinders can be tuned.

According to the present invention, the crank side of the split connecting rod is controlled by the arm, and the piston stroke can be continuously varied by changing the position of the pivot axis of the arm two-dimensionally. In addition, when continuously variable steplessly at any time, piston side pressure can be greatly reduced, low mechanical loss, top dead center phase change when changing stroke is small, and VVT for phase alignment is unnecessary, and the weight of the reciprocating motion part In addition to suppressing the increase, vibration in the direction perpendicular to the cylinder axis remains slightly, but the cylinder axis direction is balanced, greatly reducing vibration, eliminating the need for a balancer device, and reducing the crankshaft direction and reducing the center of gravity. Because it uses a single crank mechanism, it can use conventional processing equipment and the engine layout is similar. Easily mounted on conventional vehicle body, it can provide a stroke volume continuously variable device suitable for automotive engines.
In addition, since the irreversible transmission mechanism is provided in a part of the stroke volume / compression ratio variable mechanism, the stroke volume and the compression ratio can be kept constant without electric power, so that power consumption can be suppressed and fuel consumption can be reduced.

Embodiments of a continuously variable stroke volume device according to the present invention will be described below in detail with reference to the drawings. The continuously variable stroke volume device according to the present invention is applicable to power devices such as various gasoline, diesel, and HCCI engines mounted on automobiles and the like.

A variable control arm connecting shaft is provided at the apex of the connecting rod, which is divided into two and swingably connected in the direction of the crankshaft. With an L-shaped yoke, the arm connecting shaft is stroked in an arc shape with a variable control arm, and the locus approaches the top dead center side with respect to a line that is substantially parallel to the cylinder core shaft passing through the crank journal shaft core, and on the bottom dead center side. The control arm's pivot axis position is variably controlled in a two-dimensional manner so that the position and angle change radially in a square-shaped range spreading on both sides, the stroke volume is continuously variable continuously, and the compression ratio is In a continuously variable stepless variable at any time according to the stroke volume, two cranks that are reverse to each other at the same rotational speed are arranged in parallel, and the pistons connected to each crank are caused to make opposing strokes on a concentric shaft. ,crank Structure 10, the stroke volume varying mechanism 20, the stroke volume control mechanism 30, variable compression ratio mechanism 40 includes a compression ratio control mechanism 50.

The crank mechanism 10 includes a two-cylinder 180 ° phase crank R and L crankshafts 15R and 15L, in which the journal shaft core is disposed on the mating surface of the upper and middle crankcases 2 and 3 in parallel with each other. The journal shaft 15b is rotatably supported by 15-1, and a half shim is formed between the side surfaces of the journal bearing portion of the crankcase and the side surfaces of the crankshaft gear 15g and the transmission engaging boss portion 15c or the flange portion 15f. By inserting 15-2 and adjusting the thickness, the axial direction is restricted by an appropriate clearance, and the R and L crankshafts rotate in reverse at the same rotation speed by the crankshaft gear. The R crankshaft rotates clockwise and the L crankshaft rotates counterclockwise.
On the opposite crankshaft stepped shaft, R crankshaft is camshaft, camshaft drive sprocket 15d that transmits power to the oil pump, oil pump drive sprocket 15e, cam that transmits power to the camshaft on the L crankshaft The shaft drive sprocket is provided with a crank phase detection pin 15-5 for detecting the crank phase. The crank pin shaft 15a is divided into two parts and is connected to the crank side of a connecting rod which is swingably connected in a direction perpendicular to the crank shaft. The connecting rod connecting shaft 12-1 and the center of the variable control arm connecting shaft 13-4 are arranged at opposite vertices whose diagonal is substantially perpendicular to the side connecting the cores of the crankpin shaft, and the three shaft cores are L-shaped. The L-shaped yoke 13 is arranged, and half of the yoke metal bearing 13-2 and the yoke cap 13-1 are bolts. 3-3 crank pin hole formed by engaging the yoke in, rotatably supports a yoke rotatably.
The mating surface of the yoke and the yoke cap is inclined to the connecting rod connecting shaft side from the surface perpendicular to the line connecting the crank pin hole and the core of the variable control arm connecting shaft. While avoiding buffering with the rocking bearing boss part of the variable control arm 14, rigidity and strength are secured by fastening bolts between the connecting rod connecting shaft and the crank pin hole, and the mating surface is connected to the crank pin hole and the variable control arm connecting shaft. The yoke is lighter than the direction perpendicular to the line connecting the cores, reducing vibration.
Also, the I-shaped cross-section arm part of the variable control arm is also connected to the crank pin hole of the yoke and the variable control arm connection by shifting the crank pin boss part of the yoke to the side escaping with respect to the line connecting the hole core of the connecting shaft and the swinging shaft. In addition to shortening the span between shafts to reduce weight, the arm length of the variable control arm is also shortened, and the engine block is made more compact accordingly.
In this embodiment, the span between the crank pin hole of the L-shaped yoke and the variable control arm connecting shaft is increased by about 20% of the crank pin rotation diameter, and the stroke increase ratio is 1.6 or more. If the bottom dead center side of the swing track of the variable control arm swing shaft is made a track further away from the crank pin rotation track, it can be increased to about 2.
If the span is lengthened, it becomes heavier and disadvantageous in terms of strength and vibration. However, the span should be selected according to the operating characteristics of the engine.
Shortening is lighter and more advantageous in terms of strength and vibration, but the stroke increase ratio (maximum stroke / minimum stroke) decreases and the swing angle increases.
In this embodiment, the span between the variable control arm connecting shaft and the connecting rod connecting shaft is also increased by 10%. However, since the stroke amount changes in proportion to the length, the yoke is within the range where there is no problem in strength. There is an advantage that an engine with a different stroke volume can be obtained by simply changing the span. In this case, the length of the variable control arm is set to minimize the maximum piston side pressure by minimizing the trajectory of the connecting rod connecting shaft in the direction perpendicular to the cylinder core axis Y (hereinafter referred to as the Y axis) to the Y axis and making the maximum stroke uniform. There is a way to adjust by changing the height.
(See Figures 1-1 to 3)

The piston 11 is inserted into the cylinders 1R and 1L having the Y axis parallel to the concentric shaft with respect to the crankcase mating surface on which the journal shaft cores of the R and L cranks are arranged, and the piston pin 11− 1 and the connecting rod connecting shaft 12 on the piston side pivotally supported on the yoke so as to be swingable in a direction perpendicular to the crankshaft, and the variable control arm connecting shaft of the yoke pivotally supported on the crankpin shaft. The variable control arm to be controlled is pivotally supported and swung by the variable control arm swinging shaft 16 so that the variable control arm connecting shaft swings in an arc shape mainly in the Y-axis direction and passes through the crank journal axis. It regulates the direction of the axis X (hereinafter referred to as X axis) perpendicular to the Y axis and converts the piston reciprocating motion into crank rotational motion. By changing the position of the variable control arm swing shaft in two dimensions, The connecting shaft trajectory radiates in a C-shaped range that approaches the top dead center side and spreads on both sides on the bottom dead center side with respect to a line Y ′ (hereinafter referred to as Y ′ line) that passes through the crank journal axis and is substantially parallel to the Y axis. Since the position and angle are changed, and the stroke and compression ratio can be varied, the connecting rod connecting shaft swings with respect to the arm connecting shaft on the arc connecting locus of the arm connecting shaft. The vibration in the X-axis direction is suppressed to a minimum, and the lateral pressure due to the piston slap can be greatly reduced, resulting in low mechanical loss. By placing the Y-axis at the approximate center of the maximum deflection width in the X-axis direction of the connecting rod connecting shaft center swing trajectory at the minimum and maximum stroke, the piston side with respect to the Y-axis at both the top and bottom dead centers in the entire stroke range The swing angle of the connecting rod can be kept small, but in this example diagram, priority is given to forming the cylinder mating surface only with the upper crankcase and facilitating surface machining. The connecting rod connecting shaft core stroke locus is arranged at a position where the Y axis slightly deviates from the approximate center of the maximum X axis direction swing width of the connecting rod connecting shaft, and the connecting rod connecting shaft has a slightly larger shake in the X axis direction. As the number of machining steps increases, it becomes easier to create a step on the mating surface during assembly, and it is necessary to take care of the liquid seal. However, if the cylinder mating surface machining is performed simultaneously with the middle case, the maximum runout width of the Y axis in the X axis direction It is easily possible to set it to the approximate center. (See Figures 1-1 to 3)
Also, the X axis direction position at the top dead center of the arm connecting shaft is slightly shifted to set the compression ratio according to the stroke amount, but the displacement is small, so the crank phase at the top dead center due to the stroke amount Since the change is small and within a few degrees, the VVT for timing adjustment is not necessary. (See Figure 1-9)
In this embodiment, the connecting rod, the connecting rod connecting shaft, the variable control arm and the variable control arm connecting shaft are press-fitted and fixed, and each shaft is rotatably supported by both side bearing holes of the L-shaped yoke. The crankshaft counterweight is widened as much as possible, and the crankpin radius with respect to the stroke is reduced, so that the cross-sectional overlap of the crankpin shaft and journal shaft can be increased, thereby improving the rigidity and strength of the crankshaft. The rocking bearing portion is lubricated by oil supplied through oil holes communicating with the crank pin hole portion on both side bearing holes of the L-shaped yoke.
The crank mechanism is basically used together with a stroke volume variable mechanism and a compression ratio variable mechanism, which will be described later, with respect to intermediate lines C and L (hereinafter referred to as C and L) perpendicular to the line connecting the two crank journal axes when viewed in the crankshaft direction. In general, it is arranged in a line-symmetric position and moves in a line-symmetric manner. (See Figures 1-1 to 3)

The stroke volume variable mechanism 20 is configured by pivotally supporting a variable control arm swinging shaft that swingably supports a variable control arm that regulates the movement of the L-shaped yoke by a V-shaped link in the crankshaft direction view. In the one that can be positioned and fixed by point support, two end portions of the stroke volume variable link 21 on one side of the V-shaped link are close to the crank shaft center with respect to the swing shaft center position of the variable control arm. The stroke volume of the shaft centering on the mating surface of the middle crankcase and the lower crankcase 4 is parallel to the line connecting the crank journal shafts, that is, the Y ′ line and perpendicular to each crank journal shaft, and is rotatably supported. The stroke volume variable female feed screws 23R and 23L meshing with the variable male feed screw shaft 22 are pivotally supported by shafts provided at right angles to the screws, and the rotation of the female feed screw is regulated by a link. This With the rotation of the male feed screw shaft, the female feed screw slides on the male feed screw shaft, and the stroke (stroke volume) is mainly changed by changing the pivot axis position mainly in the Y-axis parallel direction. , Provided for each opposed piston mechanism arranged side by side in the crankshaft direction. Since the compression ratio changes if the swing shaft position is varied only by sliding the female feed screw of the stroke volume variable mechanism, the compression ratio variable mechanism is coordinated to vary the stroke volume at a constant or arbitrary compression ratio. Need to be moved. The stroke volume variable link having a U-shaped cross section of the arm portion is formed by sandwiching a variable control arm pivotally supported by a variable control arm swing shaft and a compression ratio variable link 41 of an H-shaped cross section arm. It is press-fitted and fixed to the attached shaft portion, and the rotation of the female feed screw is restricted by restricting the direction of the swing axis by the variable compression ratio link. (See Figures 1-1, 2, 4, and 5)

The stroke volume control mechanism 30 is provided with a driven gear portion 22b on the stroke volume variable male feed screw shaft in the vicinity of C and L, and the feed screw portions 22a on both sides of the gear are mutually reverse screws, and the stroke volume variable male feed screw for each cylinder row. In the middle of the shaft, a drive pinion shaft 33 having a driven gear portion 33b at the tip end of a shaft integrally extending in parallel with the male feed screw shaft from a pinion gear portion 33a meshing with the driven gear is used as a mating surface of the middle crankcase and the lower crankcase. A stroke volume variable mechanism for each opposed piston cylinder row is provided by arranging a shaft core and rotatably supporting the shaft core, and meshing a drive pinion gear portion 31a of a stroke volume control motor 31 fixed to a stroke volume control motor holder 32 with a driven gear portion. In conjunction with each other, variable control of all cylinder rows is possible with a single motor. The stroke volume is generally controlled by detecting the slide of the stroke volume variable female feed screw with a position sensor, but the stroke volume variable amount is large and the slide amount is large. Although this embodiment is disadvantageous in terms of cost, a control motor capable of detecting the rotation angle and the rotation amount is employed.
Shim 22-1 is disposed between the driven gear part both sides of the stroke volume variable male feed screw shaft and the bearing hole side surface part of the crankcase, and the variable control arm swinging shaft position is adjusted by adjusting the thickness of the both side shims. To adjust the stroke amount (stroke volume) of the opposed pistons. (See Figures 1-1, 2, 5, 8)

The variable compression ratio mechanism 40 is configured by pivotally supporting a variable control arm swinging shaft that swingably supports a variable control arm that restricts the movement of the L-shaped yoke with a V-shaped link as viewed in the crankshaft direction. In the one that can be positioned and fixed by point support, the tip of the link with a variable compression ratio that is farther from the crankshaft center than the swing axis of the variable control arm on one side of the V-shaped link A compression ratio variable arm 44FR, 44FL, 44RR, 44RL fixed to each cylinder row on a compression ratio variable shaft 42R, 42L arranged in parallel for each crankshaft is pivotally supported by a link pin 43 that is press-fitted and fixed to the tip. At the same time, the axial direction is restricted on the side surfaces of both sides of the compression ratio variable arm, and the tip ends of the compression ratio control levers 45R and 45L fastened to the end of the variable compression ratio shaft on the cam chain side are swung. By changing the pivot axis position of the variable control arm mainly in the X-axis direction, the compression ratio is mainly changed. The X-axis moves the variable control arm connecting shaft position at the top dead center away from the Y-axis. Displacement in the direction increases the inclination angle of the L-shaped yoke, and the connecting rod connecting shaft moves to the cylinder head side in the Y-axis direction, increasing the compression ratio. It changes relatively greatly. For example, if a combustion chamber having a maximum piston stroke of 100 mm as in this embodiment is set to a volume corresponding to the cylinder height of 11 mm of the cylinder bore, the compression ratio becomes (100 + 11) /11≈10.1. If the piston position is shifted by 5 mm and the combustion chamber volume is 6 mm, the compression ratio will be (100 + 6) /6≈17.7. Since the minimum piston stroke is 61 mm, if the combustion chamber is set to a volume equivalent to the cylinder height of 6.7 mm, the compression ratio can be equivalent to (61 + 6.7) /6.7≈10.1. If the position is shifted by 3.1 mm and the cylinder has a combustion chamber volume equivalent to 3.6 mm, the compression ratio can be equivalent to (61 + 3.6) /3.6≈17.9. As in this embodiment, in the L-shaped yoke in which the span between the crankpin hole and the variable control arm connecting shaft is increased by about 10% from the span between the variable control arm connecting shaft and the connecting rod connecting shaft, the X of the variable control arm connecting shaft The axial displacement is approximately 10% greater than the displacement of the connecting rod connecting shaft in the Y-axis direction, 5 × 1.1 / 100 = 0.055 at the maximum piston stroke, and 3.1 × 1.1 / at the minimum piston stroke. 100 ≒ 0.034, and the variable control arm swinging shaft is slightly displaced by about 3 to 6% of the maximum stroke, and it can be varied from a supercharged gasoline engine to a diesel engine or a compression ratio that enables HCCI. .
In this embodiment, the position of the link pin press-fitted into the tip of the variable compression ratio arm that pivotally supports the tip of the variable compression ratio link is set to the minimum at the same position, and the minimum compression ratio at the maximum stroke is set to the same compression ratio. At the minimum and maximum strokes, the compression ratio can be varied only by the displacement in the X-axis direction of the above-mentioned variable control arm swing shaft. However, the variable control arm swing shaft position at the same compression ratio at the intermediate stroke is connected to the variable control arm. The trajectory of the variable control arm swing shaft by swinging the compression ratio variable arm while fixing the position of the link pin press-fitted into the compression ratio variable arm is the arc of the opposite direction. Therefore, the X-axis direction displacement that adds the difference in the X-axis direction of both arcs is necessary, but it is much smaller than changing the piston stroke, so it was adopted to change the piston stroke. This system uses a feed screw mechanism for each cylinder and interlocks them, so that a shaft is arranged in parallel for each crankshaft and a separate arm is fastened to the shaft for each cylinder to change the phase of the shaft. This is superior in cost, weight, and assembly, and the crankcase can be made compact, the arm length can be changed regardless of the shaft shaft diameter, the displacement in the X-axis direction can be increased, and the variable piston ratio can be changed with a large variable piston stroke. It will be possible.
If the shaft is not on the crankcase mating surface, the shaft will be slid in the axial direction during assembly and inserted into the shaft hole of the crankcase. It is necessary to make the shaft thicker to a shaft diameter that can be limited by the amount or can secure an eccentric amount. Since the displacement amount in the X-axis direction of the swing shaft for changing the compression ratio is almost proportional to the piston stroke variable amount, that is, the Y-axis direction displacement amount, it is difficult to deal with the eccentric shaft when the piston stroke variable amount is large as in this proposal. It becomes. If the shaft can be arranged on the crankcase mating surface, it is possible to provide an integral eccentric shaft on the shaft and pivotally support the tip of the link. However, this increases the case mating surface and is disadvantageous in terms of cost and weight. Then, it is placed at a place other than the mating surface, and after placing the compression ratio variable arm in the case in advance, the compression ratio variable shaft is inserted and then tightened with the bolt 44-1, and the phase determining spline 42a is provided to obtain a predetermined phase. It is securely fixed. However, in order to provide a spline, the shaft diameter is made narrower as it becomes the insertion destination, thereby enabling insertion from one side. The oil passage liquid seal of the variable compression ratio shaft is sealed by pressing the plug 42-2 into the oil hole on the cam chain side, and the plug 4-1 is pressed into the journal shaft side case of the L side shaft on the transmission chamber side. Then, the grooved plug 42-1 is press-fitted into the oil hole on the R side shaft, and the projection of the variable compression ratio shaft phase detection sensor 55 fixed to the crankcase is faced to the groove. In addition, the compression ratio is controlled by detecting the phase of the compression ratio variable shaft.
The swinging shaft portion of the variable control arm is lubricated with oil supplied from an oil passage provided in each component of the compression ratio variable mechanism. (See Figures 1-1, 2 and 4)

The compression ratio control mechanism 50 determines the phase with respect to the compression ratio variable arm by the phase determining spline 42b provided in the stepped shaft portion near the cam chain side shaft end of the compression ratio variable shaft, and the compression ratio control levers C, L It is fastened with bolts 45-2 to the side.
On the other hand, the feed screw for converting the forward / reverse rotation of the compression ratio control motor 51 into a linear motion and swinging the compression ratio control lever is substantially the same as the line connecting the shaft axes of the variable compression ratio shafts and the shaft axis in the vicinity of C and L. Pins 54-2, which are arranged at right angles and are press-fitted and fixed to both the left and right sides of the screw shaft to the joint holder portion 54a provided at the tip of the compression ratio control male feed screw 54, and press-fitted and fixed to the tip of the control lever on both sides. One of the pins 45-1 is connected by a fixed-length joint 54-1, which is pivotally supported by the pin, and the other is an adjustment nut 54-3R, 54 which is pivotally supported by the pin. Rotate male screw adjusting bolt 54-4 with reverse screw on both sides meshing with -3L female screw, adjust span and fix with lock nut 54-5R, 54-5L to synchronize both cylinder compression ratio Possible and To have. The compression ratio control female feed screw 53 that meshes with the compression ratio control male feed screw is rotatably supported by the middle crankcase, and the axial direction is the driven gear portion 53a side at the shaft hole side surface of the middle crankcase and the upper crankcase mating surface. Part is sandwiched and regulated. A drive pinion shaft 52 having a pinion gear portion 52a meshing with the driven gear portion is disposed in parallel with the feed screw shaft in the vicinity of C and L, and is rotatably supported by bearing holes provided in the middle and upper crankcases. At the same time, the axial direction of the bearing hole is restricted. A driven gear portion 52b provided at the opposite end of the pinion gear portion of the drive pinion shaft is engaged with a drive pinion gear portion 51a of a compression ratio control motor, which is fixed to the upper crankcase with a rotation shaft arranged in parallel to the drive pinion shaft. The phase of the compression ratio variable shaft is changed by moving the male feed screw back and forth by forward and reverse rotation of the control motor, and the position of the variable control arm swing shaft is changed by the displacement of the compression ratio variable link pivotally supported at the tip of the compression ratio variable arm. The compression ratio is mainly variably controlled by displacing mainly in the X-axis direction.
(See FIGS.

In the present invention, a feed screw is provided in a part of the power transmission mechanism from the control motor of the stroke volume variable mechanism and the compression ratio variable mechanism so that the stroke volume and the compression ratio can be kept constant without power. . The lead screw may be a trapezoidal screw, square screw, sawtooth screw, etc., but in order to ensure reliable non-reversible transmission of the screw part, the screw lead angle should be less than or equal to the dynamic friction coefficient of the material used. Must be less than or equal to the static friction coefficient.

The piston stroke in FIG. 1-9 shows this embodiment, the dotted line indicates the minimum compression ratio and minimum stroke (stroke volume), and the solid line indicates the minimum compression ratio and maximum stroke (stroke volume). The crankpin phase at the point is 29 ° at the minimum stroke (stroke volume) in the direction of crank rotation from the cylinder side Y ′ line (R crank is clockwise and L crank is counterclockwise in FIGS. 1-1 and 2). Crankpin phase at 23 ° at stroke volume), 207 ° at minimum stroke (stroke volume) and 217 ° at maximum stroke (stroke volume) from top dead center, minimum and maximum stroke The time difference is not great.
Therefore, VVT for adjusting the top dead center phase is unnecessary, and the rotation angle of the intake and expansion strokes is about 30 ° larger than 180 ° (60 ° more than the compression and expansion strokes), so that the intake and expansion strokes can be made longer. However, it is disadvantageous in terms of vibration, and it is difficult to balance the primary with an in-line four-cylinder engine. If the vibration cannot be suppressed to an allowable range by a damper or the like, a device that suppresses vibration by providing a balancer, etc. However, by adopting this proposal, vibration in the direction perpendicular to the cylinder core axis remains slightly, but the cylinder core axis direction is balanced, greatly reducing vibration, eliminating the need for a balancer device, and making the crankshaft direction compact and low. It is possible to provide a continuously variable stroke volume device suitable for an automobile engine capable of achieving a center of gravity.

Hereinafter, the embodiment will be described mainly in the crankcase block portion in which the continuously variable stroke volume device at the maximum and minimum stroke (stroke volume) at the minimum compression ratio is accommodated, Oil pumps and auxiliary equipment are not shown or described.
The continuously variable stroke volume device described in the present embodiment is a naturally aspirated gasoline engine in which, in a two-crank horizontally opposed four-cylinder, one of the opposed pistons is the intake stroke during the expansion stroke and the ignition interval is 180 °. The maximum compression ratio is set at 12.0 for both the maximum stroke and the maximum compression ratio for the minimum stroke is 15.0 (when the piston top surface is aligned with the cylinder top surface). , The cylinder is upward, the stroke volume, and the compression ratio variable mechanism are mounted on the lower oil chamber side, the right side is R and the left side is L when viewed from the rear.
FIG. 1-1 shows the minimum compression ratio at the top dead center and the maximum stroke (stroke volume), the two-dot chain line on the L crank side is the connecting rod connecting shaft core locus, the one-dot chain line is the swing range of the variable control arm, the dotted line Indicates lines connecting the cores of the L-shaped yoke and the variable control arm at the bottom dead center.
FIG. 1-2 shows the minimum compression ratio and minimum stroke (stroke volume) when the front crank cylinder is at the top dead center on the L crank side, and the rear cylinder when the front crank cylinder top dead center is on the R crank side. The two-dot chain line on the L crank side indicates the connecting rod connecting axis trajectory, the one-dot chain line indicates the swing range of the variable control arm, and the dotted line indicates a line connecting the L-shaped yoke at the bottom dead center and the axis of the variable control arm. .
1-3 shows a case where the crankpin phase is on the crankcase mating surface.
In each drawing, some drawings are omitted as necessary.
The present invention is not limited to four cylinders and can be adopted from two cylinders to multiple cylinders.

FIG. 4 is a cross-sectional view (a cross-sectional view taken along the line AA in FIG. 1C) showing a minimum compression ratio and a top dead center at the maximum stroke volume in the continuously variable stroke volume device according to the present embodiment. FIG. 4 is a cross-sectional view (a cross-sectional view taken along line AB in FIG. 1C) showing a minimum compression ratio and a minimum stroke volume in the continuously variable stroke volume device according to the present embodiment, and is a right side view of C, L (L The crank side) shows the front row cylinder top dead center, and the left side (R crank side) shows the rear row cylinder at the front row top dead center. It is sectional drawing which follows the CC line of FIGS. 1-1. It is sectional drawing which follows the DD line | wire of FIGS. 1-1. It is sectional drawing which follows the EE line of FIGS. 1-1. It is sectional drawing which follows the FF line of FIGS. 1-7. It is sectional drawing which follows the GG line of FIGS. 1-6. It is sectional drawing which follows the HH line of FIGS. 1-5. It is a piston stroke figure. The crank phase is counterclockwise on the left cylinder side from the cylinder side Y 'line, the right cylinder side is clockwise (crank rotation direction), and the stroke is an example of the piston top surface height from the crank journal axis. Show. The rear row cylinder is 180 ° out of phase with the front row cylinder.

1 (R, L) Cylinder 1-1 Cylinder gasket 2 Upper crankcase 3 Middle crankcase 4 Lower crankcase 4-1 Plug 10 Crank mechanism 11 Piston 11-1 Piston pin 12 Connecting rod 12-1 Connecting rod connecting shaft 13 L-shaped yoke 13-1 Yoke Cap 13-2 Yoke Metal Bearing 13-3 Bolt 13-4 Variable Control Arm Connection Shaft 14 Variable Control Arm 15 (R, L) (R, L) Crankshaft
15a Crank pin shaft
15b Journal axis
15w counterweight part
15c Transmission engaging boss
15d camshaft drive sprocket
15e Oil pump drive sprocket
15f Isobe
15g Crankshaft gear 15-1 Journal metal bearing 15-2 Half shim 15-3 Oil seal 15-4 Seal plug 15-5 Crank phase detection pin 16 Variable control arm swing shaft 16-1 Plug 20 Stroke volume variable mechanism 21 Stroke volume variable link 22 Stroke volume variable male feed screw shaft 22a Feed screw section
22b Driven gear portion 22-1 Shim 22-2 Plug 23 (R, L) Stroke volume variable female feed screw 30 Stroke volume control mechanism 31 Stroke volume control motor 31a Drive pinion gear portion 31-1 Bolt 31-2 O-ring 32 Stroke volume control Motor holder 32-1 Gasket 32-2 Bolt 33 Drive pinion shaft 33a Pinion gear part
33b Driven gear section 40 Compression ratio variable mechanism 41 Compression ratio variable link 42 (R, L) Compression ratio variable shaft 42a Phase determining spline
42b phasing spline 42-1 -grooved plug 42-2 plug 43 link pin 43-1 plug 44 (F, R) (R, L) compression ratio variable arm 44-1 bolt 45 (R, L) compression ratio control Lever 45-1 Pin 45-2 Bolt 50 Compression ratio control mechanism 51 Compression ratio control motor 51a Drive pinion gear part 51-1 O-ring 52 Drive pinion shaft 52a Pinion gear part
52b Driven gear part 52-1 Thrust washer 53 Compression ratio control female feed screw 53a Driven gear part 54 Compression ratio control male feed screw 54a Joint holder part 54-1 Joint 54-2 Pin 54-3 (R, L) Adjustment nut 54-4 Adjustment bolt 54-5 (R, L) Lock nut 55 Compression ratio variable shaft phase detection sensor Y Cylinder axis Y 'Line passing through the crank journal axis and substantially parallel to the Y axis X Passing through the crank journal axis and perpendicular to the Y axis Axis C, L Intermediate line perpendicular to the line connecting the two crank journal axes when viewed from the crankshaft direction

A variable control arm connecting shaft is provided at the apex of the connecting rod, which is divided into two and swingably connected in the direction perpendicular to the crankshaft. L-shaped yoke, the arm connecting shaft is stroked in an arc shape by the variable control arm, and the locus approaches the top dead center side with respect to the line substantially parallel to the cylinder core shaft passing through the crank journal shaft core. The control arm's pivot axis position is variably controlled in a two-dimensional manner so that the position and angle change radially within a square-shaped range extending on both sides, and the stroke volume is continuously variable continuously and the compression ratio. In which two cranks that are mutually reversed at the same rotational speed are arranged in parallel, and pistons connected to the cranks are opposed to each other on a concentric shaft. In the class Click mechanism 10, the stroke volume varying mechanism 20, the stroke volume control mechanism 30, variable compression ratio mechanism 40 includes a compression ratio control mechanism 50.

The crank mechanism 10 includes a two-cylinder 180 ° phase crank R and L crankshafts 15R and 15L, in which the journal shaft core is disposed on the mating surface of the upper and middle crankcases 2 and 3 in parallel with each other. The journal shaft 15b is rotatably supported by 15-1, and a half shim is formed between the side surfaces of the journal bearing portion of the crankcase and the side surfaces of the crankshaft gear 15g and the transmission engaging boss portion 15c or the flange portion 15f. By inserting 15-2 and adjusting the thickness, the axial direction is restricted by an appropriate clearance, and the R and L crankshafts rotate in reverse at the same rotation speed by the crankshaft gear. The R crankshaft rotates clockwise and the L crankshaft rotates counterclockwise.
On the opposite crankshaft stepped shaft, R crankshaft is camshaft, camshaft drive sprocket 15d that transmits power to the oil pump, oil pump drive sprocket 15e, cam that transmits power to the camshaft on the L crankshaft The shaft drive sprocket is provided with a crank phase detection pin 15-5 for detecting the crank phase. The crank pin shaft 15a is divided into two parts and is connected to the crank side of a connecting rod which is swingably connected in a direction perpendicular to the crank shaft. The connecting rod connecting shaft 12-1 and the center of the variable control arm connecting shaft 13-4 are arranged at opposite vertices whose diagonal is substantially perpendicular to the side connecting the cores of the crankpin shaft, and the three shaft cores are L-shaped. The L-shaped yoke 13 is arranged, and half of the yoke metal bearing 13-2 and the yoke cap 13-1 are bolts. 3-3 crank pin hole formed by engaging the yoke in, rotatably supports a yoke rotatably.
The mating surface of the yoke and the yoke cap is inclined toward the connecting rod connecting shaft side from the surface perpendicular to the line connecting the crank pin hole and the core of the variable control arm connecting shaft, and the clamping boss portion of the yoke cap fixing bolt during crank rotation While avoiding collision with the rocking bearing boss part of the variable control arm 14, the connecting rod connecting shaft and the crank pin hole are secured with bolts to secure rigidity and strength, and the mating surface is connected to the crank pin hole and the variable control arm connecting shaft. The yoke is lighter than the direction perpendicular to the line connecting the cores, reducing vibration.
Also, the I-shaped cross-section arm part of the variable control arm is also connected to the crank pin hole of the yoke and the variable control arm connection by shifting the crank pin boss part of the yoke to the side escaping with respect to the line connecting the hole core of the connecting shaft and the swinging shaft. In addition to shortening the span between shafts to reduce weight, the arm length of the variable control arm is also shortened, and the engine block is made more compact accordingly.
In this embodiment, the span between the crank pin hole of the L-shaped yoke and the variable control arm connecting shaft is increased by about 20% of the crank pin rotation diameter, and the stroke increase ratio is 1.6 or more. If the bottom dead center side of the swing track of the variable control arm swing shaft is made a track further away from the crank pin rotation track, it can be increased to about 2.
If the span is lengthened, it becomes heavier and disadvantageous in terms of strength and vibration. However, the span should be selected according to the operating characteristics of the engine.
Shortening is lighter and more advantageous in terms of strength and vibration, but the stroke increase ratio (maximum stroke / minimum stroke) decreases and the swing angle increases.
In this embodiment, the span between the variable control arm connecting shaft and the connecting rod connecting shaft is also increased by 10%. However, since the stroke amount changes in proportion to the length, the yoke is within the range where there is no problem in strength. There is an advantage that an engine with a different stroke volume can be obtained by simply changing the span. In this case, the length of the variable control arm is set to minimize the maximum piston side pressure by minimizing the trajectory of the connecting rod connecting shaft in the direction perpendicular to the cylinder core axis Y (hereinafter referred to as the Y axis) to the Y axis and making the maximum stroke uniform. There is a way to adjust by changing the height.
(See Figures 1-1 to 3)

Hereinafter, the embodiment will be described mainly in the crankcase block portion in which the continuously variable stroke volume device at the maximum and minimum stroke (stroke volume) at the minimum compression ratio is accommodated, Oil pumps and auxiliary equipment are not shown or described.
In the continuous stroke volume variable device described in the present embodiment, in a two-crank horizontally opposed four-cylinder, one of the front-row cylinder-opposed pistons takes the other during the expansion stroke, and the other of the rear-row cylinder-opposed pistons takes the other compression stroke. Is a naturally aspirated gasoline engine with an exhaust stroke of 180 ° and an ignition interval of 180 °. The minimum compression ratio is 12.0 at the minimum and maximum stroke, and the maximum compression ratio is 15.0 at the minimum stroke. When the vehicle is mounted with the cam chain chamber on the front, the transmission chamber on the rear, the cylinder on the upper side, the stroke volume, and the compression ratio variable mechanism on the lower oil chamber side, the right side as viewed from the rear is R. , L on the left side.
FIG. 1-1 shows the minimum compression ratio at the top dead center and the maximum stroke (stroke volume), the two-dot chain line on the L crank side is the connecting rod connecting shaft core locus, the one-dot chain line is the swing range of the variable control arm, the dotted line Indicates lines connecting the cores of the L-shaped yoke and the variable control arm at the bottom dead center.
FIG. 1-2 shows the minimum compression ratio and minimum stroke (stroke volume) when the front crank cylinder is at the top dead center on the L crank side, and the rear cylinder when the front crank cylinder top dead center is on the R crank side. The two-dot chain line on the L crank side indicates the connecting rod connecting axis trajectory, the one-dot chain line indicates the swing range of the variable control arm, and the dotted line indicates a line connecting the L-shaped yoke at the bottom dead center and the axis of the variable control arm. .
1-3 shows a case where the crankpin phase is on the crankcase mating surface.
In each drawing, some drawings are omitted as necessary.
The present invention is not limited to four cylinders and can be adopted from two cylinders to multiple cylinders.

Claims (5)

A variable control arm connecting shaft is provided at the apex of the connecting rod, which is divided into two and swingably connected in the direction perpendicular to the crankshaft. L-shaped yoke, the arm connecting shaft is stroked in an arc shape by the variable control arm, and the locus approaches the top dead center side with respect to the line substantially parallel to the cylinder core shaft passing through the crank journal shaft core. In the two-dimensional variable control of the position of the swing axis of the variable control arm so that the position and angle change radially within a square shape extending on both sides, The two cranks are arranged in parallel, the pistons connected to each crank are made to make opposing strokes on the concentric shaft, and the pivot axis position of the variable control arm is set on the opposite side of the opposing piston cylinder with respect to the two cranks. Clan of books Stroke volume continuously variable device for variably controlling arranged in line symmetry with respect to perpendicular median line to the line connecting the journal axis. The swing shaft of the variable control arm is pivotally supported by a link in a V-shape when viewed from the crankshaft direction, and can be positioned and fixed by three-point support. The tip of the link is pivotally supported by a female feed screw that meshes with a male feed screw shaft that is arranged parallel to the line connecting the two crank journal shaft axes and perpendicular to each crank journal shaft. By restricting the rotation of the female feed screw, the female feed screw slides on the male feed screw shaft by the rotation of the male feed screw shaft, and the pivot axis position is mainly changed in the cylinder axis parallel direction. The stroke volume continuous variable device according to claim 1, wherein the stroke volume is variable. In the case where the opposed piston mechanisms are arranged side by side in the crankshaft direction, a gear is provided on the male feed screw shaft near the intermediate line perpendicular to the line connecting the two crank journal shaft cores, and the feed screws on both sides of the gear are reversely screwed to each other. A shaft is formed by disposing an idle gear in the middle of the male feed screw shaft for each cylinder row and meshing it, and integrally extending from one end of the idle gear in parallel to the male feed screw shaft. A driven gear is provided at the tip of the cylinder, and the drive gear of the variable stroke volume control motor is meshed with the variable stroke volume mechanism for each opposed piston cylinder row, enabling variable control of all cylinder rows with a single motor. The stroke volume continuous variable apparatus according to claim 2. The swing shaft of the variable control arm is pivotally supported by a link in a V-shape when viewed from the crankshaft direction, and can be positioned and fixed by three-point support. The tip of the link is pivotally supported by the tip of an arm fixed for each cylinder row on the shaft arranged in parallel for each of the two crankshafts, and the tip of the control lever fixed to the shaft is also oscillated. The continuous stroke volume variable device according to claim 1, wherein the compression ratio is mainly varied by varying the pivot axis position of the variable control arm mainly in a direction perpendicular to the cylinder axis. Both sides of the feed screw that converts the rotation of the compression ratio control motor into a linear motion and swings the compression ratio variable control lever is fixed near the middle line perpendicular to the line connecting the two crank journal axes. It is arranged at a right angle to the line connecting the shaft axis and the shaft axis, and the length of at least one of the joints connecting the leading end of the feed screw and both control levers can be adjusted, and the compression ratio of both cylinders can be synchronized. The stroke volume continuous variable apparatus according to claim 4.

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